Detergent



Patented Feb. 12, 1946 DETERGENT Harland H. Young and Kurt n. Spitnnueller,

Chicago, 111., assignors to Industrial Patents Q Corporation, Chicago, 111., a corporation of Delaware No Drawing. Application August 10, 1942,

' Serial No. 454,303 I I 6 Claims.

This invention relates to certain new chemical compounds and to the method of preparing such I compounds. The compounds are surface active agents and are particularly adapted for use as detergents, wetting agents, foaming agents, emulsifiers and the like.

Soaps, that is alkali metal salts of the higher 'fatty acids, are perhaps the best known and most widely used detergents. As is well known, soaps have certain inherent-disadvantages, particularly when employed in the presence of acids or in the presence of calcium and magnesium salts. For example, soap in the presence of hard waters containing'calcium and magnesium salts forms precipitates which are troublesome in many instances. Also, any salt solution if sufficiently concentrated can exert a salting' out efiect which tends to grain out" the soap.

The synthetic detergents have been developed to provide detergents, wetting agents and the like such as to warrant the increased cost.

In recent years many so-called synthetic detergents have been prepared and marketed. In general, these substances have a hydrophylic group and a lipophilic group linked by various types of intermediate groups. A great number of the synthetic detergents or surface active agents conhalog en atom with a sodium sulphonate radical. The chlorinated sulphonated product is then acylated preferably with a fatty acid salt whereby the remaining halogen is replaced with an acid radical.

In a similar manner, various synthetic detergents have been prepared in which the base or starting material consists of polyhydric alcohols having at least three hydroxyl groups such as glycerin. Alpha-chlorohydrin may be treated with a sulphonating agent such as an aqueous solution of sodium sulphite and the resulting product reacted with an acylating substance such as fatty acids or acid chlorides to form a product in which one of the halogens has been replaced by a sodium sulphonate radical and the other by a lipophilic group derived from a fatty acid. The polyhydric alcohol residue which forms the link between these two groups contains at least one free hydroxyl group.

Synthetic detergents have also been prepared from ethers. However, the methods employed are quite costly and produce low yields of the synthetic detergent. A dihalogenated other is re- 5 acted with an aqueous solution of a sulphonating halogen is replaced by nitrogen with the formation of an amino-ether sulphonic acid. The amino radical is then acylated with an acid, acid chloride, or an acid anhydride to insert into the compound a lipophilic group. These compounds,

.35 although they are efiective detergents and surface tain a sulphate or sulphonate radicalas the hydrophylic group. The lipophilic group may consist of a fatty alcohol residue, a fatty acid ester residue and many detergents have been proposed in which the lipophilic group has been derived from esters of polyhydric alcohols. In most instances, the hydrophylic group consists of the sodium sulphate or sulphonate radical rather than the sulphuric or sulphonic acid radical itself.

Various detergents have been prepared and proposed in which the base or starting material consists of a dihydroxy alcohol. The dihydroxy alcohol is esterified with hydrogen halide whereby the hydroxyl groups are replaced by halogen such as chlorine, bromine or iodine. The halogenated product is then treated with a sulphonating agent, for example, with an aqueous solution of sodium sulphite, under such conditions as to replace one active agents, are quite costly because the yield is low and the more effective of these 'compounds involve the use of amines and acid chlorides or acid anhydrides. If the inexpensive fatty acids are employed as the acylating substances, the yield of product and quality are so low that the resulting cost is quite high based upon the effectiveness of the product.

One of the objects of the present invention is to provide a synthetic detergent which is superior a detergent containing the grouping as the hydrophylic group when R is hydrogen or a small alkyl group, :c is a small whole number and C, H, S, O and Na are carbon, hydrogen,

sulphur, oxygen and sodium respectively.

Another object of this invention is to provide a method of preparing such detergents or surrived from ethers, which method produces excellent yields and produces a product requiring little if any refining.

Otherobjects and advantages of this invention will become apparent from the detailed description and claims which follow.

The present invention contemplates the preparation of acylated sulphonated others by converting a dihalogenated ether to a monosulphonate-monohalogenated ether and the subsequent acylation of the remaining halogen whereby this halogen is replaced by a lipophilic radical derived from acyl or alkyl hydroxy compounds.

' We have discovered that the compounds prepared in accordance with our method and which possess an ether linkage in the residue which joins the hydrophylic and lipophilic groups apear to have a better balance between the groups whereby the compounds are more effective than those compounds in which the linkage between the two groups contain hydroxyl or other groups or substituents. For example it has been found that the ether linkage is more polar than a free hydroxyl group. A further characteristic of our compounds is that they are not easily hydrolyzable by alkali to form non-detergent bodies whereas compounds such as sulphated fatty alcohols and the like are quite readily hydrolyzable to form non-detergent bodies. Also it is unnecessary to substitute into the compound at any stage of the preparation an amine or amino group, and it is unnecessary to employ acid anhydrldes or acid chlorides to increase yields.

The ethers which we may use as base or starta ing materials include ethers derived from the polymerization of mixed polyhydric alcohols such as glycerol and glycols, polymeric polyhydric alcohols such as diethylene glycol, dipropylene glycol, triethylene glycol, polyethylene glycols, diglyoerol and thelike. Corresponding thio compounds or sulphur analogues are also satisfactory for the purposes of our invention but are not preferred for reasons of cost and odor. The ethers are halogenated to form dlhalog'en derivatives or commercial dihalogen derivatives may be employed as initial materials for the subsequent preparation of our surface active agents. The only limitations in this respect are that the halogen atoms must be reactive toward the sulhonating agent and the subsequent acylating agent, and that the halogen atoms are sensitive to metathesis or hydrolysis.

In practicing the invention a polyhydroxy ether is -first converted into a dichloride, or if desired certain dichlorides which are available commercially may be employed in the first instance. The dichloride is then converted to a monosulphonatemonocnloride by reaction of the dichloride with a suitable sulphonating agent such as sodium sulphite. The reaction is carried out in water, but due to the immiscibility of the materials the reaction is relatively slow. order to promote miscibility and to increase the speed of reaction, alcohol may be added; such as ethyl alcohol, methyl alcohol, isopropyl alcohol or other homologues. The reaction may also be hastened by the use of higher boiling oint solvents and we prefer to employ solvents such as methyl, ethyl, or propyl mono ethers of ethylene glycol. Any mutual solvent for the dichloride and water will increase the speed of reaction but in selecting the mutual solvent the boiling point of the solvent and ease of recovery should be considered. In the reaction the sodium sulphite reacts with one of the chlorine atoms whereby sodium chloride splits out and the sulphonate of the monochloride is formed. Since it is desired to replace but one of the halogen or chlorine atoms, care should be exercised so as to prevent hydrolysis of the second chlorine atom by water which is present or by metathesis with any excess sodium sulphite.

We have discovered that the resulting monohalogenated-monosulphonated ether or derivative may be reacted with an alkali metal derivative of a lipophilic compound. The alkali metal is preferably sodium or potassium although other alkali metals are satisfactory in some instances. The lipophilic compound may be selected from a large group of substances which may be defined as acyl and alkyl hydroxy lipophilic compounds whose metal derivatives are not appreciably decomposed in the presence of water. A convenient class of acyl derivatives may be derived from the fatty acids preferably those acids having at least twelve carbon atoms, however in certain instances it may be desirable to employ acids having a lesser number of carbon atoms. The acyl compounds are usually soaps such as sodium and potassium oleates, palmitates, stearates, laurates, myristates and the like. It is common knowledge that such soaps may be prepared by neutralization of the particular fatty acid. A mixture of the individual soaps may be prepared, for example, by neutralization of the fatty acids derived from various animal, vegetable and marine fats and oils or their hydrogenation products, or the soaps may be prepared by the direct reaction between the alkali and the animal, vegetable, or marine fat or oil, or their hydrogenation products. Convenient and very satisfactory soaps for the purposes of the present invention may be derived from tallow, cocoanut 011, cottonseed oil and hydrogenated cottonseed oil. Other fats and oils and their hydrogenation products .are also satisfactory. In general, we prefer to employ soaps derived from fatty or lipophilic or carboxylic acids having from 16 to 18 carbon atoms. The acyl compounds may also include hydroxy acids and these may be desired for certain specific applications of the detergent I compounds.

As stated heretofore, the class of alkali metal derivatives 'of lipophilic compounds which may be reacted with the monohalogenated-monosullphonated ether also includes alkyl hydroxy do lipophilic com-pounds whose alkali metal salts are are satisfactory for the purposes of our invennot appreciably decomposed by water. Examples of such alkyl compounds include lauryl, myristyl, palmityl and stearyl alcohols. The alkali metal derivatives such as the sodium derivatives tion. Other alcohols such as secondary alcohols may also be used.

The reaction between the sodium derivative of the lipophilic compound and the monohalogenated-monosulphonated ether is effected by fusion with or without the presence of water depending on whether the alkali metal derivative is decomposed by water. If the alkali metal derivative is not decomposed by water, it may be melted or fused in the presence of water and and the water were distilled from the mass.

the monohalogenated-monosulphonated ether or derivative is mixed with the fused soap in the presence of moisture. This reaction is a simple metathesis of the second halogen atom. Fusion of the monohalogenated-monosulphonated ether individually cannot be effected since these compounds decompose at their fusion temperature more rapidly than the desired metathesis takes place.

For purposes of illustration a more detailed description of the operation of the invention will now be given.

The dichloride of diethylene glycol may be employed as the starting material and a convenient form of this compound is the commercial 22' dichlor diethyl ether. If diethylene glycol-is employed, the glycol is first converted into the dichloride. The dichloride is mixed with a saturated aqueous solution of sodium sulphite and with sufficient mutual organic solvent for the water and the dichloride so as to produce a homogeneous product. In one specific example, ethyl alcohol was employed as the mutual solvent. In other examples, we have successfully employed isopropyl alcohol and methyl, ethyl, propyl, monoethers of ethylene glycol. The mass was then refluxed at the boiling point of the solution and the refluxing continued until a sample of the solution disclosed that all sodiur'n sulphite had been consumed. In carrying out this reaction the dichloride and sodium sulphite were employed in approximately stoichiometric proportions. We prefer to employ an excess of the dichloride so as. to force the'formation of the monosulphonic acid derivative predominantly. In this reaction one of the chlorine atoms is replaced by the sodiuni, sulphonate radical and sodium chloride is split out.

At the completion of the reaction the excess dichloride of the diethylene glycol, the alcohol In this reaction a small amount of the dichloride is converted to the disulphonate. The material remaining after the volatile matter has been distilled off contains the monochloride-monosulphonate, sodium chloride and a small amount of thedisulphonate. The sodium chloride and the disulphonate may be allowed to remain in the mass or separated, as desired. These substances, of course, constitute impurities in the final product. The mass may be dried and the monochloride-monosulphonate may be extracted with an alcohol or other suitable solvent such as a cellosolve, ethyl alcohol, isopropyl alcohol, acetone and the like. The monochloride-monosulphonate may then be recovered in relatively pure state from the solution.

The monochloride-monosulphonate, either in the pure state or containing the disulphonate and sodium chloride impurities, is then fused with soap in the presence of moisture or water. The soap preferably consists of a sodium or potassium salt of higher fatty acids such as oleic, palmitic, stearic, lauric, myristic acids and the like. The soap may be prepared by reacting the alkali with the fattyacid or by the neutralization of fatty acids derived from animal, vegetable and marine fats and oils and their hydrogenation products, or by the reaction of the alkali with the fat or oil or hydrogenation products of the fats and -oils. The soap should contain some moisture and in general should contain at least 5 per cent water. It is not necessary, however, that the soap contain that quantity of moisture since in certain individual instances lesser quantities are satisfactory. In general, we prefer to employ soap containing between 20 per cent and per cent moisture. However, here again, the amount may vary and greater quantities of moisture may be desired for certain specific instances.

The monochloride-monosulphonate and soap are reacted inequimolar quantities and yield an acylated monosulphonate ether. The soap is fused and the monochloride-monosulphonate mixed with the fused soap. The temperature of the fusion step may vary from about 180 F. to about 300 F. and is dependent upon the individual soap and upon the moisture content. The monochloridemonosulphonate decomposes at its fusion temperature but we have discovered that if this material is added to soap in the presence of moisture or water no decomposition occurs. It would be expected that the presence of moisture or water would hydrolyze the chlorine to form a corresponding alcohol. We have discovered, however, that if the monochloride-monosulphonate is added to fused soap in the presence of moisture, such hydrolysis does not occur, but that the chlorine reacts with the alkali met'al of the soap to form an acylated sulphonated ether.

Other ethers and dichlor ethers may be employed in a manner similar to that described above. Also sodium derivatives of alkyl compounds such as the alcoholates may be employed in the fusion step instead of soaps, in which case the moisture should be absent during this fusion step if the alcoholate is decomposed by water. The particular temperature of fusion will depend upon the individual alkyl derivative and upon the molecular ratio of the reactants.

By our method, it is possible to eliminate the costly steps and procedure of introducing nitrogen into the compounds by means of expensive amines and of using acid chlorides or acid anhydrides for the insertion of lipophilic groups into the compounds. Also, it is unnecessary by our method to employ a sodium soap since any neutral water soluble soap is satisfactory.

The products obtained by our method may be employed in hard waters without the formation of characteristic precipitates and form clear sudsy solutions in the presence of alkalies, acids and in various brines. Also our products have the advantage of producing results equal or superiorv to those of ordinary soap when used in soft water in smaller amounts than soap.

A compound prepared from the dichloride of ethylene glycol and tallow has been found to be highly effective for washing purposes. In soft water this derivative appears to be equal to that of soap and in many instances appears to have a greater detergent potency than soap. In hard water this product is superior to soap since there is no formation of any insoluble precipitates or scums.

Obviously, many modifications and variations of the inventionhereinbefore set forth may be made without distinguishing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

We claim: 1. As a composition of matter, a chemical com pound consisting of an acyclic aliphatic ether having a sulphonate radical connected with a terminal alkyl radical on one side of the ether link age and a lipophillic radical selected from the group consisting of acyclic aliphatic, acyl and acyclic aliphatic alkyl hydroxy radicals con nected with a terminal alkyl radical on the oppo= site side of the ether linkage.

2. A composition of matter as described inclaim 1 in which the acyl radical is aiatty acid grouping.

3. A composition of matter as described in 

